Live timer

Speaker timer for live streams: an iPad (huge countdown), a TV (countdown + YouTube live chat + polls + live duration) and an admin page, all synced over the local network. No dependencies: just Node.js.

Using it? Read READ ME FIRST.txt: install Node.js, double-click Start Timer.

Layout

• Start Timer.command — double-click launcher (keeps the Mac awake, restarts the server after an update)
• app/server.js — HTTP + Server-Sent Events server (timer state, controls, settings)
• app/youtube-chat.js — reads the YouTube live chat, polls and live duration (no API key)
• app/updater.js — live updates from this GitHub repository
• app/public/ — iPad (/), TV (/tv) and admin (/admin) pages
• app/settings.json, app/runtime-state.json — this Mac's settings and current countdown (not in git)
• tests/ — automated tests

Live updates

Every Mac running the timer checks this repository every 5 minutes. When main has a new commit, the admin shows Update available → Install now. Installing downloads that exact commit, checks that the code parses, swaps the files (keeping settings.json and the running countdown), and restarts the server in ~2 s; every screen reloads by itself. Publishing an update = pushing to main, so run the tests before pushing.

Tests

node --test tests/*.test.js

Server stress tests (malformed requests, 200 screens, 600 simultaneous clicks, crash/restart mid-countdown), YouTube chat reader tests against a fake YouTube (reconnects, timeouts, moderation, both poll formats), a chat endurance test (thousands of polling cycles with every kind of failure: every message must arrive exactly once), the screen timer (hours of simulated countdown, connection loss, clock jumps) and live updates (fake GitHub).

tests/fixtures/fake-youtube.js can be loaded into the real server (NODE_OPTIONS="--require ./tests/fixtures/fake-youtube.js") for an end-to-end soak with an endless chaotic chat.